Author: John Rydning, Research Director, Hard Disk Drives
Storage device options continue to broaden for disk storage system OEMs and end users. For enterprise applications, hard-disk drives (HDDs) are now available in several form factors, configured with parallel SCSI, Fibre Channel, Serial ATA (SATA) or Serial Attached SCSI (SAS) interfaces. An increasing number of solid state drives (SSDs) are now also shipping for enterprise applications. DRAM-based SSDs have for many years satisfied the needs of very high performance, latency-sensitive environments, but at a high cost. Now, with the price decline in NAND flash and advances in technology, NAND-based SSDs have a growing opportunity in the datacenter. Similar to HDDs, flash-based SSDs are offered with several interface options.
Today's diversity of storage device options for the datacenter contrasts sharply with the limited selection available just five years ago. Consider the changes that have taken place just with hard disk drives. In 2003, essentially two HDD form factors serviced the large percentage of enterprise datacenter storage demands: 3.5 inch 10,000 rpm and 3.5 inch 15,000 rpm HDDs. Today, in addition to these 3.5 inch enterprise class products, the HDD industry also ships 2.5 inch 10,000 and 15,000 rpm enterprise-class small-form-factor (SFF) drives. Collectively, IDC classifies these drives as performance-optimized HDDs. By 2009, 2.5 inch performance-optimized HDDs will out-ship 3.5 inch products.